**Question:**

**An alpha-particle of mass $m$ suffers 1 -dimensional elastic collision with a nucleus at rest of unknown mass. It is scattered directly backwards losing, $64 \%$ of its initial kinetic energy. The mass of the nucleus is :**

$2 \mathrm{~m}$

$3.5 \mathrm{~m}$

$1.5 \mathrm{~m}$

$4 \mathrm{~m}$

Question of from chapter.

JEE Main Previous Year 12 Jan. 2019

Correct Option: 4

**Solution:**

### Related Questions

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